1. Field of the Invention
The invention is related to a touch display apparatus, and in particular, to an optical touch display apparatus.
2. Description of Related Art
With the rapid advancement of optoelectronic technologies, a user may no longer be satisfied with the use of a mouse to control a computer and objects on a screen. Accordingly, interfaces more user-friendly than the mouse have been gradually developed. Among these user-friendly interfaces, the touch control method by using fingers is closest to human experiences in the daily life. In particular, elders and children who may be incapable of using the mouse nimbly may touch with their fingers easily. This has been partially proved by the adoption of touch screens in some automatic teller machines.
Additionally, if a mouse is not externally connected to a conventional laptop computer, the cursor is controlled through the track pad and track point beside the keys. For a general user, however, the track pad or track point beside the keys may not be controlled as nimbly as the mouse, whereas a touch device disposed on the screen may solve such a problem. Since the control method of the touch device is a very intuitive control method, and the user directly touches the screen to control the objects. Hence, when the touch device is applied to the laptop computer, even if it is inconvenient for the user to externally connect the mouse, the user is still capable of agilely controlling the laptop computer through the touch device.
Currently, general touch devices may be classified into resistive types, capacitive types, optical types, acoustic wave types, and electromagnetic types. An optical touch display apparatus generally includes a display, an infrared light source, a light guide unit, a detector, and a processor, wherein the display includes a backlight module and a display panel. The infrared light source is disposed beside the display panel to generate an infrared beam capable of being detected by the detector after passing through the light guide unit. The processor determines the position of the touch object according to an intensity change in the infrared beam detected by the detector when a touch object contacts the panel. However, since the infrared light source and the light guide unit used to guide the infrared light are disposed on a front frame beside the display panel, the structure beside the display panel protrudes too much, thereby causing the appearance of the display to be inferior and lack a smooth and modernistic touch. Moreover, a plurality of sets of infrared light sources and light guide units are required, thereby causing increases in the number of optical components and costs, and assembly times are also lengthened.